The generation of patterns and the stitching of the generated patterns on fabric or other materials utilizing computer control has been developed. The generated patterns are stored, for example, on appropriate tape for inputting to a computerized controller. Alternatively, one or more predetermined patterns are stored in computer memory using printed circuit boards or other memory storage devices. In another known method of stitching patterns, a predetermined pattern is stored in computer memory and a computer controller includes the capability of providing axis translation of the predetermined pattern so that more than one stitch pattern is available. For example, mirror image stitch patterns can be provided from one predetermined stitch pattern.
Prior to the present invention, in the case of stitching characters along a curve including an arc, the desired pattern of characters positioned along an arc was initially formulated and then this pattern was stored in computer memory. Upon activation, the sewing machine was able to stitch the fabric with the desired pattern using the character pattern stored in the computer memory. The same stitching of characters along an arc could be repeated as many times as desired. However, if different character patterns along a different arc were desired, for example, a new and different stitch pattern was required to be formulated and then stored in the computer memory. The forming of different stitch patterns by an operator for memory storage is a long and tedious procedure. A considerable number of different stitch points must be defined in order to instruct the computer system regarding the location of the new stitch pattern.
The present invention obviates this cumbersome process and eliminates the requirement for storing different stitch points in memory each time a different stitch pattern along an arc is desired. The present invention provides a method and an apparatus for stitching characters, including letters, along a curve, including an arc. The method disclosed herein does not require a memory-stored predetermined stitch pattern in order to stitch characters on fabric along a curve. Rather, the method requires that a user or operator provide necessary inputs to the apparatus. Among the required inputs, the operator selects the characters to be stitched, the magnitude of curvature or radius of the arc along which the selected characters are to be stitched, the direction of the stitching, namely, clockwise or counterclockwise, and the magnitude of a center angle which is used to determine the angular stitch position of the selected characters with reference to 360.degree..